ZOECon tickets question

I got our trip all booked (staying at the Red Lion, but we're also going to be there a few days beforehand to explore the area and sight-see, that kind of thing).
I registered our tickets, and was wondering if the tick-boxes for various events are more of an interest-gauge or if we'll be able to change our minds and attend things we didn't check off on that list once we're there?

Edit: Also, will it present any issues that I didn't reserve the room through the ZOEcon link in the email?